Tankless Water Heater 

Error Code “29”

Our homes have tankless water heaters, and these systems have an “evaporation drain” pipe that drips on the outside of our homes (outside wall behind/near the water heater).

The water dripping from the evaporation pipes can freeze and prevent the tankless system from heating the water. When this happens, you cannot get hot water from your faucets inside your home, and your tankless system display shows “error code 29”.

Homeowners need to warm up and “thaw” the pipe outside the house, which should clear the error code and allow the system to provide hot water again. You may have to thaw the pipe repeatedly during prolonged freezing weather.

If you cannot get ANY water into the house during freezing weather, it may be that the pipes within the wall of the garage have frozen somewhere. The pipes will need to be thawed by warming up the walls from within the garage.

For more tips about preventing frozen pipes see: How to Prevent Your Pipes From Freezing – Consumer Reports